<nav>
    <ul class="pager" style="margin-top:3px;margin-bottom:3px;">
        <li class="previous"><a href="{{site.production_url}}{{ page.previous.url }}">&larr; 上一篇</a></li>
        <li class="next"><a href="{{site.production_url}}{{ page.next.url }}">下一篇 &rarr;</a></li>
    </ul>
</nav>